/*
* Copyright 2017 Anton Tananaev (anton@traccar.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.traccar.protocol;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.traccar.BaseProtocolDecoder;
import org.traccar.DeviceSession;
import org.traccar.helper.BitUtil;
import org.traccar.helper.UnitsConverter;
import org.traccar.model.Position;
import java.net.SocketAddress;
import java.nio.ByteOrder;
import java.nio.charset.StandardCharsets;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;
public class DmtProtocolDecoder extends BaseProtocolDecoder {
public DmtProtocolDecoder(DmtProtocol protocol) {
super(protocol);
}
public static final int MSG_HELLO = 0x00;
public static final int MSG_HELLO_RESPONSE = 0x01;
public static final int MSG_DATA_RECORD = 0x04;
public static final int MSG_COMMIT = 0x05;
public static final int MSG_COMMIT_RESPONSE = 0x06;
@Override
protected Object decode(
Channel channel, SocketAddress remoteAddress, Object msg) throws Exception {
ChannelBuffer buf = (ChannelBuffer) msg;
buf.skipBytes(2); // header
int type = buf.readUnsignedByte();
buf.readUnsignedShort(); // length
if (type == MSG_HELLO) {
buf.readUnsignedInt(); // device serial number
DeviceSession deviceSession = getDeviceSession(
channel, remoteAddress, buf.readBytes(15).toString(StandardCharsets.US_ASCII));
if (channel != null) {
ChannelBuffer response = ChannelBuffers.dynamicBuffer(ByteOrder.LITTLE_ENDIAN, 0);
response.writeByte(0x02); response.writeByte(0x55); // header
response.writeByte(MSG_HELLO_RESPONSE);
response.writeShort(4 + 4);
response.writeInt((int) (System.currentTimeMillis() / 1000));
response.writeInt(deviceSession != null ? 0 : 1); // flags
channel.write(response);
}
} else if (type == MSG_COMMIT) {
if (channel != null) {
ChannelBuffer response = ChannelBuffers.dynamicBuffer(ByteOrder.LITTLE_ENDIAN, 0);
response.writeByte(0x02); response.writeByte(0x55); // header
response.writeByte(MSG_COMMIT_RESPONSE);
response.writeShort(1);
response.writeByte(1); // flags (success)
channel.write(response);
}
} else if (type == MSG_DATA_RECORD) {
DeviceSession deviceSession = getDeviceSession(channel, remoteAddress);
if (deviceSession == null) {
return null;
}
List<Position> positions = new LinkedList<>();
while (buf.readable()) {
int recordEnd = buf.readerIndex() + buf.readUnsignedShort();
Position position = new Position();
position.setProtocol(getProtocolName());
position.setDeviceId(deviceSession.getDeviceId());
position.set(Position.KEY_INDEX, buf.readUnsignedInt());
position.setDeviceTime(new Date(1356998400000L + buf.readUnsignedInt() * 1000)); // since 1 Jan 2013
position.set(Position.KEY_EVENT, buf.readUnsignedByte());
while (buf.readerIndex() < recordEnd) {
int fieldId = buf.readUnsignedByte();
int fieldLength = buf.readUnsignedByte();
int fieldEnd = buf.readerIndex() + (fieldLength == 255 ? buf.readUnsignedShort() : fieldLength);
if (fieldId == 0) {
position.setFixTime(new Date(1356998400000L + buf.readUnsignedInt() * 1000));
position.setLatitude(buf.readInt() * 0.0000001);
position.setLongitude(buf.readInt() * 0.0000001);
position.setSpeed(UnitsConverter.knotsFromCps(buf.readUnsignedShort()));
buf.readUnsignedByte(); // speed accuracy
position.setCourse(buf.readUnsignedByte() * 2);
position.set(Position.KEY_PDOP, buf.readUnsignedByte() * 0.1);
position.setAccuracy(buf.readUnsignedByte());
position.setValid(buf.readUnsignedByte() != 0);
} else if (fieldId == 2) {
int input = buf.readInt();
int output = buf.readUnsignedShort();
int status = buf.readUnsignedShort();
position.set(Position.KEY_IGNITION, BitUtil.check(input, 0));
position.set(Position.KEY_INPUT, input);
position.set(Position.KEY_OUTPUT, output);
position.set(Position.KEY_STATUS, status);
} else if (fieldId == 6) {
while (buf.readerIndex() < fieldEnd) {
switch (buf.readUnsignedByte()) {
case 1:
position.set(Position.KEY_BATTERY, buf.readUnsignedShort() * 0.001);
break;
case 2:
position.set(Position.KEY_POWER, buf.readUnsignedShort() * 0.01);
break;
case 3:
position.set(Position.KEY_DEVICE_TEMP, buf.readShort() * 0.01);
break;
case 4:
position.set(Position.KEY_RSSI, buf.readUnsignedShort());
break;
case 5:
position.set("solarPower", buf.readUnsignedShort() * 0.001);
break;
default:
break;
}
}
}
buf.readerIndex(fieldEnd);
}
if (position.getFixTime() == null) {
getLastLocation(position, position.getDeviceTime());
}
positions.add(position);
}
return positions;
}
return null;
}
}